The benefits of a tripod, fast lens, shooting at base ISO, and an advanced camera.

Or, you could shoot at 1/3 second at ISO 3200, hand held, with image stabilization; and then live with the fuzzy edges and noise.

As the class says, good lighting helps a lot and eliminates the need for the fast lens and the tripod, and maybe even the advanced camera technology. Good light also eliminates the need to know that you need a fast lens and a tripod and the better camera.
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Jerry

It is, you just haven't factored in 'time'.When you expose at 10s at f/1.8, you're going to let in a lot of light regardless. When they say you need 'light', they mean that you need to control the light that you have.

Also, f/1.8 is very unoptimal for the lens. Since you were shooting on a tripod, you could have made the same exposure at 30s and f/4 and would have achieved an even sharper image.

What are the "deciding" factors for shutter speed in "low light" or "poor light"?

How would the same photo look like if I were to keep the shutter open for 1 minute or 2 minutes? Too Overexposed?

Well today's DSLR cameras can meter pretty well out to about 30 seconds. So it is likely that the camera's meter was used either in aperture priority mode, or as a baseline to get the exposure in manual mode.

This picture is exposed nearly perfectly IMHO and increasing the exposure from 10 seconds to 1 minute would increase the exposure by about 2.5 stops. If you didn't compensate for that increase by changing the ISO (can't in this case as it already is at ISO100) or aperture, then the picture would be overexposed.